This invention relates to the antiviral usage of flavopereirine. More specifically, it relates to a pharmaceutical preparation whose sole active ingredient is flavopereirine, and to the use of this preparation for the treatment of viral infections in human--in particular, infections such as those provoked by the Human Immunodeficiency Virus (HIV).
Flavopereirine is an alkaloid of the beta-carboline class. It is also traditionally referred to as "H or PB 100 composition," and shows UV emission fluorescence at 250-254 and 306 nm.
Flavopereirine may be obtained from the peel of the Pao Pereira Geissospermum vellosii-Baillon Apocynaceae (see H. Rapaport et al., J. Amer. Chem. Soc. 80:1601-1608 (1958) and Beljanski et al., request for first certificate of addition #79 05853 to French patent application #78 07155 and EP-A-0 059 817.).
It is known that flavopereirine, administered intracutaneously at a dosage of 200-600 .mu.g or a dosage of 2.5-500 mg/day, preferably 30 mg/day, prevents the appearance and development of vital papules in the case of viruses of the Shope fibrome type and of vaccine.
It is also known that flavopereirine appears to act in vivo against influenza (RNA virus), and that it may moreover inhibit the multiplication of the tobacco mosaic virus (TMV) after brief contact with this virus.
European Patent Application EP-A-0 059 817 reveals that flavopereirine is active against the influenza virus; however, the half-life of a quaternary beta-carboline of this type is too short for efficient use in humans in a galenic form other than time-release capsules.
French Patent Application No. 88 15845 describes a system for improving immune defense in humans (against RNA viruses--AIDS in particular--and DNA viruses). According to this document, the inhibition of the multiplication of the viruses in question is possible only by a combination of four different substances, of which flavopereirine is only one. The pharmaceutical preparation revealed in the document must include at least one representative of each of these four categories of active substances. The flavopereirine included in this combination is administered at a dosage of 0.25 g/day, preferably orally.